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91.
    
Teftoon, a flat bread made of whole wheat flour, is prepared by hand sheeting of dough, followed by baking. Different emulsifiers, like lecithin, E471 (distilled monoglyceride) and E472 (diacetylated tartaric acid esters of mono- and digelycerid of fatty acids), were added to the flour at various levels ranging between 0.25 and 1.0% w/w, and it was observed that they improved the dough characteristics. Improvement in bread quality parameters, such as force to tear and sensory acceptability, were monitored. Fungal α -amylase was also incorporated into the flour at 5–20 g/100 kg flour basis alone and in combination with the emulsifier. The force required to tear the fresh bread was decreased with emulsifier and enzyme addition; however, E472 addition at 0.75% w/w of whole wheat flour gave the softest bread. The tear force of stored bread significantly increased with storage; however, bread containing E472 showed a less increase in tear force up to a period of 3 days. The sensory acceptability was found to be higher than that of the control bread for emulsifiers, and lower for enzyme at a concentration higher than 10 g/kg flour.

PRACTICAL APPLICATIONS


Flat bread is normally consumed fresh, but the staling phenomenon starts immediately after baking this kind of bread. Today, large-scale production and increased consumer demands for high-quality bread with long shelf life have created the need for functional food additives such as emulsifiers and α -amylase enzyme. Incorporation of emulsifiers and enzyme decreased the hardness of Taftoon bread. Emulsifiers and α -amylase enzyme enhanced the flat bread dough quality. The sensory acceptability also improved with the addition of emulsifiers. Optimizing the amount of emulsifiers and enzyme required for reduction of bread hardness is vital because the quality and price of the final product depend on this parameter.  相似文献   
92.
    

ABSTRACT

A total of 100 fresh‐cheese‐based desserts (Hosmerim and Cheese helva) from nine different production areas in Marmara Region of Turkey were studied. There were no statistically significant differences in microbiological composition between Hosmerim and Cheese helva. Mean values of APC, Staphylococcus aureus, molds, yeasts, osmophilic yeasts for Hosmerim were 5.7 × 104, 8.0 × 102, 1.8 × 103, 2.8 × 103, 1.6 × 103 cfu/g, respectively, while coliform bacteria, Escherichia coli and Bacillus cereus were <10 cfu/g. Results for Cheese helva were slightly higher. Salmonella spp. and staphylococcal enterotoxin were not detected in 25 g of any sample. Cheese helva, however, had a significantly lower pH and significantly higher contents of protein, fat and carbohydrates, and thus, also a higher content of dry matter. Within each product category, a large variation was observed for both microbiological counts as well as for the chemical composition. This indicates a lack of standardization in the manufacturing process and prompts for the establishment of appropriate process control measures.

PRACTICAL APPLICATIONS

The aim of this study was to determine the chemical and hygienic quality traits of traditional cheese desserts, namely Cheese helva and Hosmerim. For this purpose, 50 Cheese helva and 50 Hosmerim samples obtained from different regions in Turkey were analyzed on account of their microbiological, physico‐chemical and toxicological properties. The presence of some pathogens in the samples and the variable chemical composition indicate that the production process should be defined in “Codes of Good Manufacturing Practice” and the product characteristics should be codified in order to achieve a product with a defined level of microbiological safety.  相似文献   
93.
    
Ninety‐five isolated strains of Lactic acid bacteria (LAB) were identified from Lighvan cheese. The LAB evolution showed the dominance of lactococci and lactobacilli in the first stage and substitution of these genera by enterococci at the end of ripening. The most predominant strains were Enterococcus faecium (22.44%), Lactococcus lactis ssp. lactis (20.4%), Lactobacillus plantarum (18.36%) and E. faecalis (14.28%), respectively. Eleven and 51 different carbohydrate fermentation profiles were observed according to API 20 STREP and API 50 CH, respectively. API 20 STREP dendogram showed identical fermentation profiles of some E. faecalis and E. faecium strains, indicating that these strains might be well adapted to the whole cheese manufacture.  相似文献   
94.
    
The development of free fatty acids (FFA) and volatile flavour compounds in the Turkish white‐brined cheese Beyaz peynir made by using three wild strains of Lactococcus lactis subsp. lactis was investigated over 90 days. Results showed that production of both FFA and flavour compounds in the control (PK1) and experimental cheeses (MBLL9, MBLL23 and MBL27) was strain dependent. The hydrolysis of milk fat was more evident in the cheese made using Lc. lactis subsp. lactis MBL27. Considering the production of fat breakdown compounds and acidification activities of the strains MBLL23 and MBL27, the combination of these strains could be proposed for the production of white‐brined cheese.  相似文献   
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97.
    
Physicochemical characteristics of traditional Tunisian butter (TTB) and thermal stability of the butter oil were studied. Thermal stability of samples was estimated by using the accelerated shelf life testing method. Effect of heating on some quality characteristics of traditional Tunisian butter oil (TTBO) was investigated and compared at different temperatures (60°C, 100°C and 130°C). Induction period of sample heated at 60°C was important compared to that at 100°C and 130°C. This result may indicate the sensitivity of TTBO to elevated temperature. Absorption at 232 and 270 nm, acidity and PV increased rapidly after reaching the oxidation induction time. The temperature had a significant effect on the formation of oxidation products in traditional butter oil (TTBO). Fatty acid composition of TTBO was also changed after heating. This may explain the observed modification on some quality characteristics of TTBO such as viscosity, hardness, cohesiveness and colour. As a consequence, heat treatment produced alterations in the oxidative status of the butter oil that could affect the shelf life.  相似文献   
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99.
The headway between vehicles in a traffic stream is of fundamental importance in traffic engineering applications. Previous research in this subject has focused on modeling theoretical distributions for low and medium traffic flow conditions. Yet little research has studied congested traffic conditions, that is, the high traffic flow state. In the same context, there appears to be a lack of clear-cut boundaries for the three flow states (low, medium, and high). This study attempts to determine such boundaries on the basis of traffic conditions observed at the study sites. Although observed headways at arterial sites follow a gamma distribution, distributions that fit freeway headways differ according to the traffic flow state. The Erlang distribution provided a good fit to the observed headways at sites with high traffic flows.  相似文献   
100.
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Dynamic operation and control of power system is being increasingly done with the help of phasor measurement unit(PMU) based wide area monitoring and control system. The data communication requirements for the PMU based applications are well addressed by IEEE C37.118.2 standard. However, IEC 61850 is now becoming a leading standard for power utility automation needs. A new part of IEC 61850, IEC 61850-90-5, specifying the IEEE C37.118.1 based synchrophasors data transfer according to IEC 61850, will lead to IEC 61850-90-5 based PMU communication networks. A novel IEC 61850-90-5 compliant communication model of PMU is proposed in this paper. We also present a comparative performance analysis of the PMU communication networks supporting the new synchrophasor standard for data transfer, i.e. IEC61850-90-5, and the existing standard, i.e. IEEE C37.118.2, for end to end(ETE) delay requirements for a modified IEEE 30 bus test system.  相似文献   
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